Lightning talks are usually 5 minutes and have the purpose of presenting an idea very quickly and succinctly. If users enjoy the topic, they can follow the links you provide for more information. For example: MongoDB demo, the latest changes in jQuery 1.4, testing JS with QUnit, etc. http://javascriptchicago.com/?p=162

Meetups are structured as two consequential sessions with networking opportunities planned after each session. First session targets members who are new to JavaScript, the next session being for advanced presentations.